A comparison of methods for assessing patient body burden following 131I therapy for thyroid cancer.

Abstract

The effectiveness of three methods of assessing the patient body burden following 131I therapy was compared: (a) urine assay, (b) external exposure rate measurements, and (c) predictions based on a pretherapy diagnostic work-up. The urine assay method exhibited the greatest potential for error and personnel risk. The diagnostic work-up provided predictions of the body burden as a function of time, which may be applied to estimate the expected hospital stay. The direct external exposure rate survey showed the potential for being an accurate, reliable, and relatively safe method of monitoring the patient body burden.

Estimation of effective half life of clearance of radioactive Iodine ( 131 I) in patients treated for hyperthyroidism and carcinoma thyroid

“…thyroid patients in the present work, an estimated effective half time of clearance of 14.4 h for body burden is in good agreement with the earlier reported value 11.2-15.4 h[5] in Indian population, and the values reported by Barrington et al ,[4] viz. 9.4 h, 13.4 h and 12 h. Thomas et al ,[1] compared three methods of body burden estimation viz. 1) urine assay 2) prediction based on a pre-therapy diagnostic work up method using 74 MBq (2 mCi) 3)external exposure rate measurements during actual treatments.…”

“…[1–5] Present regulations in Oman[6] indicates the need for hospitalization of patients above 400 MBq administered activities of RA 131 I. We have only two isolation rooms connected with delay tank facility for I-131 treatments.…”

Toxicity from treatment of neuroblastoma with 131I-meta-iodobenzylguanidine

“…1986;Benua et al 1962). In each patient, the whole body retention of tracer doses was compared with that obtained from a portable ionization chamber survey meter (Cutie pie) which gave readings of whole body radioactivity after the therapy dose (Thomas et al 1980). The absorbed dose of beta radiation in the whole body was calculated from the activity retained at the serial points of measurement assuming a uniform distribution of 131[ throughout the body (Berlin 1968).…”

Thyroid Cancer: Radiation Safety Precautions in131I Therapy Based on Actual Biokinetic Measurements

“…Whole-body activity retention.-The time-dependent whole-body DRs were fit by minimizing x 2 and were used to deduce nonphysical decay-corrected whole-body activity retention (24). The initial DR (IDR) (defined as the whole-body DR measured before any activity excretion) obtained at 1 m was converted to be the baseline quantification with 100% of the administered activity.…”